Grass Lake, MI climate
Grass Lake has chilly, snowy winters and pleasant summers. A typical July afternoon reaches 82°, a January night drops to 16°, and about 33 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decade2° warmer than normal today. The forecast high is 69°, and a typical Sep 30 in Grass Lake peaks around 67°.Live forecast: National Weather Service · Normal: NOAA 1991–2020
What a year in Grass Lake feels like
Winter
Spring
Summer
Fall
Grass Lake weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 31° | 16° | 2.2" | 10.9" | 13 | 20 | 14° – 34° |
| February | 34° | 17° | 1.9" | 8.6" | 10 | 16 | 11° – 35° |
| March | 44° | 26° | 2.2" | 4.7" | 9 | 7 | 26° – 49° |
| April | 58° | 36° | 3.2" | 0.9" | 11 | 1 | 40° – 52° |
| May | 69° | 47° | 3.9" | 0 | 12 | 0 | 50° – 64° |
| June | 79° | 56° | 3.9" | 0 | 10 | 0 | 63° – 72° |
| July | 82° | 60° | 3.3" | 0 | 9 | 0 | 66° – 77° |
| August | 80° | 58° | 3.6" | 0 | 9 | 0 | 64° – 74° |
| September | 73° | 51° | 2.9" | 0 | 9 | 0 | 56° – 66° |
| October | 61° | 40° | 3.0" | 0 | 11 | 0 | 47° – 57° |
| November | 47° | 30° | 2.6" | 1.8" | 10 | 2 | 32° – 46° |
| December | 35° | 22° | 2.0" | 6.0" | 11 | 11 | 16° – 39° |
| Year | 58° | 38° | 34.7" | 32.9" | 123 | 56 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in Grass Lake
Grass Lake gets 35 inches of rain and melted snow a year. May is the wettest month and February the driest. Rain or snow falls on about 123 days a year. Snow covers the ground about 56 days of the year.
About 163 frost-free days a year
In half of years the last 32° night comes by April 30 and the first one by October 12. That leaves about 163 frost-free days for gardens, shorter than 68% of U.S. towns.
Heating and cooling a home in Grass Lake
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Grass Lake, 92% of that work is heating and 8% is cooling, so the furnace matters far more than the air conditioner.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
Grass Lake and its neighbors
Grass Lake borders 6 towns with climate data. January nights across them vary by 0.4°. Sharon has the coldest January nights (16°) and Norvell the hottest July afternoons (83°). Grass Lake’s January low is 16° and its July high 82°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Grass Lake compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in Grass Lake averaged 1.6° warmer than the 1900s. The biggest change is in December (+3.1°). The shift is larger than in 76% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Grass Lake’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. February swings the most: between 1991 and 2020 its average temperature ranged from 11° to 35°. June is the most reliable, staying within 9°.
Common questions about Grass Lake’s climate
What is the coldest month in Grass Lake?
January, with a typical high of 31° and a low of 16°.
What is the hottest month in Grass Lake?
July, with a typical high of 82° and a low of 60°. About 11 days a year reach 90°.
How much snow does Grass Lake get?
About 33 inches in a normal winter, most of it in January.
When is the first frost in Grass Lake?
In half of years the first 32° night comes by October 12, and the last spring frost by April 30.
What is the rainiest month in Grass Lake?
May, with 3.9 inches of rain and melted snow. The year totals 35 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Grass Lake itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Chelsea, MI (11 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.